no sweat. thats how we learn. well, on a good cart, the cold and hot areas are insulated from the rest of the cart, so your hotbox dont heat up your whole cart. of course some companys dont even insulate at all. stay away from those. you can tell by running the burners for a while, and if the rest of the cart starts getting hot, that is bad. your cart can get how enoght to burn people and your cold drink bin will go thru ice like satan trying to get a cold drink. so basicly, what/where ever you cut, make sure the insulation is replaced. to even tell if it has any thou, you can open up a door close to the hotbox and shove your arm in there and feel for it. but some people insulate the outside of the box, and some might put the box in a insulated bin too. it’s hard to say what a manufactor will do. just be carefull. you can end up with someone elses problems and have to do a lot of stuff to it.